Fix false path warnings with resources.PostProcess

Fixes #7735

4 files changed, 61 insertions, 13 deletions

diff --git a/commands/hugobuilder.go b/commands/hugobuilder.go
index 71992e409..3e96bfc73 100644
--- a/commands/hugobuilder.go
+++ b/commands/hugobuilder.go
@@ -45,7 +45,6 @@ import (
 	"github.com/gohugoio/hugo/resources/page"
 	"github.com/gohugoio/hugo/tpl"
 	"github.com/gohugoio/hugo/watcher"
-	"github.com/spf13/afero"
 	"github.com/spf13/fsync"
 	"golang.org/x/sync/errgroup"
 	"golang.org/x/sync/semaphore"
@@ -419,18 +418,6 @@ func (c *hugoBuilder) build() error {
 			return err
 		}
 
-		if c.r.printPathWarnings {
-			hugofs.WalkFilesystems(h.Fs.PublishDir, func(fs afero.Fs) bool {
-				if dfs, ok := fs.(hugofs.DuplicatesReporter); ok {
-					dupes := dfs.ReportDuplicates()
-					if dupes != "" {
-						c.r.logger.Warnln("Duplicate target paths:", dupes)
-					}
-				}
-				return false
-			})
-		}
-
 		if c.r.printUnusedTemplates {
 			unusedTemplates := h.Tmpl().(tpl.UnusedTemplatesProvider).UnusedTemplates()
 			for _, unusedTemplate := range unusedTemplates {
diff --git a/hugolib/hugo_sites_build.go b/hugolib/hugo_sites_build.go
index c552b9de8..ea73c493f 100644
--- a/hugolib/hugo_sites_build.go
+++ b/hugolib/hugo_sites_build.go
@@ -143,6 +143,21 @@ func (h *HugoSites) Build(config BuildCfg, events ...fsnotify.Event) error {
 		if err := h.render(infol, conf); err != nil {
 			h.SendError(fmt.Errorf("render: %w", err))
 		}
+
+		if h.Configs.Base.LogPathWarnings {
+			// We need to do this before any post processing, as that may write to the same files twice
+			// and create false positives.
+			hugofs.WalkFilesystems(h.Fs.PublishDir, func(fs afero.Fs) bool {
+				if dfs, ok := fs.(hugofs.DuplicatesReporter); ok {
+					dupes := dfs.ReportDuplicates()
+					if dupes != "" {
+						h.Log.Warnln("Duplicate target paths:", dupes)
+					}
+				}
+				return false
+			})
+		}
+
 		if err := h.postProcess(infol); err != nil {
 			h.SendError(fmt.Errorf("postProcess: %w", err))
 		}
diff --git a/testscripts/commands/hugo__path-warnings-postprocess.txt b/testscripts/commands/hugo__path-warnings-postprocess.txt
new file mode 100644
index 000000000..0677da084
--- /dev/null
+++ b/testscripts/commands/hugo__path-warnings-postprocess.txt
@@ -0,0 +1,20 @@
+hugo --printPathWarnings
+
+! stdout 'Duplicate'
+
+-- hugo.toml --
+-- assets/css/styles.css --
+body {
+  background-color: #000;
+}
+-- content/p1.md --
+-- content/p2.md --
+-- content/p3.md --
+-- layouts/index.html --
+Home.
+-- layouts/_default/single.html --
+{{ $css := resources.Get "css/styles.css" }}
+{{ $css := $css | minify | fingerprint | resources.PostProcess  }}
+CSS: {{ $css.RelPermalink }}
+{{ .Title }}
+
diff --git a/testscripts/commands/hugo__path-warnings.txt b/testscripts/commands/hugo__path-warnings.txt
new file mode 100644
index 000000000..f7e3acd95
--- /dev/null
+++ b/testscripts/commands/hugo__path-warnings.txt
@@ -0,0 +1,26 @@
+hugo --printPathWarnings
+
+stdout 'Duplicate'
+
+-- hugo.toml --
+-- assets/css/styles.css --
+body {
+  background-color: #000;
+}
+-- content/p1.md --
+---
+url: /p1/
+---
+-- content/p2.md --
+---
+url: /p1/
+---
+-- content/p3.md --
+---
+url: /p1/
+---
+-- layouts/index.html --
+Home.
+-- layouts/_default/single.html --
+Single.
+